A new video released by Keystone XL pipeline opponents shows a powerful logging machine dropping a tree perilously close to a protester in a Texas forest.

It's the latest confrontation between environmental protesters and energy giant TransCanada -- and it comes as GOP presidential nominee Mitt Romney makes immediate approval of Keystone XL front and center in his economic pitch to voters.

The incident, which lasted a few seconds, was filmed Tuesday near Winnsboro, Texas, and posted to YouTube Thursday. Members of a group called Tar Sands Blockade are using civil disobedience tactics to halt pipeline construction on land that TransCanada is clearing through the threat of eminent domain. Some activists are camping in trees while others are getting in front of backhoes and log cutters.